Method and device for preventing solid products from adhering to inner surface of exhaust gas pipe and exhaust gas treatment device with the device

ABSTRACT

A solid product removal apparatus for removing a solid product adhering to an gas exhaust pipe member has a rinsing water inlet pipe member having a tip opening located inside the gas exhaust pipe member for feeding rinsing water into the inside of the gas exhaust pipe member from the tip opening thereof. The solid product removal apparatus is particularly useful when exhaust gas contains an ingredient capable of forming a solid product upon reaction with water inside the gas exhaust pipe member and can rinse off the solid product adhering to the inner face of the gas exhaust pipe member with rinsing water. A plurality of tip openings may be provided for the rinsing water inlet pipe member in a relationship so as to be spaced apart at a given interval along a direction of flow of the exhaust gas, and when a solid product formed upon reaction with a moisture inside the gas exhaust pipe member and adhering to the inner face of the gas exhaust pipe member is rinsed with rinsing water introduced one of the plural tip openings, a solid product formed newly upon reaction with the rinsing water and adhering thereto can be rinsed off with the rinsing water introduced from another tip opening located at a different position. Further, an adherence of the solid product can be prevented by heating the inner face of the gas exhaust pipe member. Moreover, a scraping member means for scraping the solid product stuck to the inner face of the gas exhaust pipe member may be provided in the gas exhaust pipe member so as to be slidably movable in the gas exhaust pipe member.

TECHNICAL FILED

[0001] The present invention relates to a method and an apparatus forpreventing adherence of a solid product in a gas exhaust pipe memberand, more particularly, to a method and an apparatus suitable forpreventing adherence of a solid product in a gas exhaust pipe member forleading an exhaust gas discharged from a semiconductor manufacturingapparatus to an exhaust gas abatement device.

BACKGROUND TECHNOLOGY

[0002]FIG. 17 illustrates a layout of a general-type exhaust gas removalapparatus for a semiconductor manufacturing apparatus. In asemiconductor manufacturing apparatus 100, semiconductor substrates areprocessed using a variety of processing gases in a vacuum chamber 102,and the processing gas is discharged from the vacuum chamber 102 with avacuum pump 104 and fed to an exhaust gas abatement device 106 connectedto a downstream side (an outlet side) of the vacuum pump. The hazardousgas is then processed to become a non-hazardous gas that in turn is fedto an gas exhaust duct 108. As the exhaust gas contains an ingredienthaving a low vapor pressure at ambient temperature, it may becomesolidified at the time when the pressure downstream of the vacuum pump104 elevates, and may then adhere to an exhaust pipe member and becomedeposited thereonto. For instance, such an ingredient may include but isnot limited to aluminum chloride (AlCl₃) discharged in an etchingprocess for aluminum wiring, ammonium chloride (NH₄Cl) derived in aprocess for forming a film of silicone nitride (SiN) or titan nitride(TiN), and tetraethyl silicate (TEOS) used in forming a film of siliconeoxide (SiO₂).

[0003] Further, the exhaust gas may contain an ingredient that mayproduce a solid product upon reaction with water. For instance, such aningredient may include but be not limited to BCl₃ to be used in etchingfor aluminum wiring, and SiCl₄ to be discharged upon etching apolysilicon with a Cl-type gas. These solid products may be stuck to anexhaust pipe member close to an inlet of the exhaust gas abatementdevice and deposited thereon because humidity in the gas exhaust pipemember becomes high in the case where the exhaust gas abatement deviceis of a wet type using water for the removal of a hazardous ingredient.

[0004] The adherence and deposit of the solid products in the pipemember may be generally prevented, for example, by winding an exteriorportion of the gas exhaust pipe member for flowing exhaust gas with aheater and heating the gas exhaust pipe member or other processes.

[0005] The gas exhaust pipe member, however, is provided, for example,with a variety of valves or branch pipe members and a bypass pipe memberconnecting an upstream side (an inlet side) to a downstream side (anoutlet side) of the exhaust gas abatement device, and so on, and thepipe construction may be rendered complex at many points, and thus itbecomes difficult to wind the heater around the pipe member as a wholein an appropriate fashion. Therefore, problems may result, for instance,that a solid product may adhere to and deposit inn a valve unlikely tobe heated or that a solid product may adhere to a portion of the pipemember where flow of an exhaust gas may slow due to a complicated pipeconstruction. Moreover, in the case where the exhaust gas abatementdevice for processing exhaust gas into a non-hazardous gas is of a wettype where the exhaust gas is brought into contact with water, ahumidity may become too high at a portion of the pipe member close tothe inlet of the exhaust gas abatement device, whereby it may becomeimpossible to heat the portion thereof to a sufficiently high degree. Inparticular, in the case where the exhaust gas contains an ingredientproducing a solid product upon reaction with water, it may present theproblem that the solid product formed due to such a high level ofhumidity is likely to adhere to and deposit on the portion of the pipemember.

[0006] In view of the foregoing problems, the present invention has beenmade with the object of providing a method and an apparatus forpreventing adherence and deposit of a solid product in a gas exhaustpipe member for discharging exhaust gas.

DISCLOSURE OF THE INVENTION

[0007] The present invention provides a solid product removal apparatusfor removing a solid product adhering to an inner face of a gas exhaustpipe member, which is characterized by a rinsing water inlet pipe memberwith a tip opening disposed at the tip of the gas exhaust pipe memberpositioned therein so as to feed rinsing water from the tip opening tothe inner face of the gas exhaust pipe member. The term “rinsing waterinlet pipe member” referred to herein includes not only a single pipemember simply for introducing rinsing water, but also a means forallowing rinsing water to flow from the outside into the inside of thegas exhaust pipe member, including a hole disposed through a pipe wallof the gas exhaust pipe member, which can receive the rinsing water fedfrom a pipe member for introducing the rinsing water into the inside ofthe gas exhaust pipe member and allow the rinsing water to pass thereto.

[0008] The solid product removal apparatus is useful particularly withan exhaust gas containing an ingredient forming a solid product uponreaction with water present in the gas exhaust pipe member, since it isable to wash off the solid product formed and stuck to the inner face ofthe pipe member with a rinsing water.

[0009] The rinsing water inlet pipe member may be disposed on aperiphery of the gas exhaust pipe member and provided with a ring-shapedrinsing water jacket member receiving rinsing water. The tip opening atthe tip of the rinsing water inlet pipe member may be formed as aplurality of holes communicating with the rinsing water jacket memberand further with the pipe wall of the gas exhaust pipe member andextending into the inside of the gas exhaust pipe member (disposed in arelationship spaced apart at given intervals in a peripheral directionof the gas exhaust pipe member).

[0010] More preferably, a heating means for heating the gas exhaust pipemember may be provided to evaporate rinsing water remaining in theinside of the gas exhaust pipe member by heating after introduction ofthe rinsing water. This is to prevent any fresh solid product from beingformed with the rinsing water remaining in the inside of the gas exhaustpipe member.

[0011] The rinsing water inlet pipe member may be disposed in pluralnumbers, and the tip openings of the rinsing water inlet pipe membersmay be formed at a spaced relationship at predetermined intervals alonga flow path of exhaust gas in the gas exhaust pipe member. Thisstructure allows a fresh solid product formed and stuck upon reactionwith rinsing water in the gas exhaust pipe member to be washed off withrinsing water introduced from a tip opening or openings at a differentposition or positions, when a solid product formed and adhering uponreaction with water in the gas exhaust pipe member is washed withrinsing water introduced from the tip opening at a given position. It isto be noted, however, that a single tip opening can perform a similarrinsing action. This can be done by changing a range of distribution ofrinsing water by adjusting a pressure of discharging rinsing water fromthe tip opening. From this point of view, the present invention can alsoprovide a method for rinsing a solid product in the manner as describedabove. More specifically, this method is characterized by a step ofrinsing off a primary solid product formed upon reaction with moisturecontained in an exhaust gas present on the inside of the gas exhaustpipe member by feeding a primary rinsing water, and a step of rinsingoff a secondary solid product formed freshly upon reaction with theprimary rinsing water adhering to the inside of the gas exhaust pipemember by feeding a secondary rinsing water.

[0012] Further, the present invention provides a solid product removalapparatus for removing a solid product stuck on an inner face of a gasexhaust pipe member, characterized by a high-temperature gas inlet meansfor heating the inside of the gas exhaust pipe member by introducing ahigh-temperature gas having a high temperature in the gas exhaust pipemember. Heating the inside of the gas exhaust pipe member may prevent adeposit of a solid product. The high-temperature gas inlet means may bedisposed in such a manner that an opening thereof for discharging thehigh-temperature gas is formed so as to discharge the high-temperaturegas toward a given location inside the gas exhaust pipe member, forexample, a location at which a valve unlikely to be heated easily ismounted.

[0013] Moreover, the present invention provides a solid product removalapparatus for removing a solid product stuck to the inner face of thegas exhaust pipe member, which is characterized in that a scrapingmember means is disposed inside the gas exhaust pipe member so as to beslidably movable in the gas exhaust pipe member along the lengthwisedirection thereof and which can scrape the solid product stuck to theinside of the gas exhaust pipe member.

[0014] In addition, the present invention provides an exhaust gasprocessing system for use in the preparation of semiconductors, which ischaracterized by a semiconductor manufacturing apparatus having a vacuumchamber for processing the semiconductors therein, a vacuum pump fordischarging gas for use in the vacuum chamber from the vacuum chamber, awet-type exhaust gas abatement device for processing the exhaust gasdischarged from the vacuum pump to turn it into a non-hazardous gas, afirst pipe member connecting the semiconductor manufacturing apparatusto the vacuum pump, a second pipe member connecting the vacuum pump tothe exhaust gas abatement device and extending a connecting portion tobe connected to the semiconductor manufacturing apparatus in a verticaldirection, and a solid product removal apparatus disposed at theconnecting portion of the second pipe member extending in the verticaldirection for removing the solid product formed upon reaction of theexhaust gas with moisture from the wet-type exhaust gas abatement deviceand stuck on the inner face of the connecting portion, wherein the solidproduct removal apparatus has substantially the same construction as thesolid product removal apparatus for removal of the solid product in thegas exhaust pipe member as described above.

BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS

[0015]FIG. 1 is a view showing an example of a construction of anexhaust gas abatement device for carrying out a method for preventing anadherence of a solid product in the gas exhaust pipe member inaccordance with the present invention.

[0016]FIG. 2 is a view showing another example of a construction of anexhaust gas abatement device for carrying out a method for preventing anadherence of a solid product in the gas exhaust pipe member inaccordance with the present invention.

[0017]FIG. 3 is a view showing an example of a construction of anapparatus for preventing the adherence of a solid product in the gasexhaust pipe member in accordance with the present invention.

[0018]FIG. 4 is a view showing an example of a construction of anapparatus for preventing the adherence of a solid product in the gasexhaust pipe member in accordance with the present invention.

[0019]FIG. 5(a) is a conceptual view showing a conventional apparatuswith a heater wound on an outer side of a gas exhaust pipe member.

[0020]FIG. 5(b) is a conceptual view showing an apparatus for flowing aninert gas having a high temperature into a gas exhaust pipe member inaccordance with the present invention.

[0021]FIG. 6 is a view showing an example of a construction of awet-type exhaust gas abatement device with the solid product removalapparatus for removing a solid product in the gas exhaust pipe member inaccordance with the present invention.

[0022]FIG. 7 is a view showing an example of a construction of a solidproduct removal apparatus in accordance with the present inventionmounted on the wet-type exhaust gas abatement device of FIG. 6.

[0023]FIG. 8 is a view showing an example of a construction of a solidproduct removal apparatus in accordance with the present inventionhaving the construction similar to the apparatus of FIG. 7.

[0024]FIG. 9 is a view showing a further example of a differentconstruction of a solid product removal apparatus in accordance with thepresent invention.

[0025]FIG. 10 is a view showing a further example of a differentconstruction of a solid product removal apparatus in accordance with thepresent invention.

[0026]FIG. 11 is a view showing another example of a construction of awet-type exhaust gas abatement device with the solid product removalapparatus in accordance with the present invention.

[0027]FIG. 12(a) is a view showing an example of a construction of asolid product removal apparatus for removal of a solid product in thegas exhaust pipe member in accordance with the present invention.

[0028]FIG. 12(b) is a view showing a solid product removal apparatus,similar to FIG. 12(a), which is provided with one rinsing water inletpipe member.

[0029]FIG. 12(c) is an illustration showing a state of the formation ofa solid product without solid product removal apparatus provided.

[0030]FIG. 13 is a view showing an example of the disposition of a tipopening of a rinsing water inlet pipe member in the solid productremoval apparatus in accordance with the present invention.

[0031]FIG. 14 is a view showing an example of rinsing work with thesolid product removal apparatus of FIG. 12(a).

[0032]FIG. 15 is a view showing a further example of a construction of awet-type exhaust gas abatement device provided with a solid productremoval apparatus for removal of the solid product in the gas exhaustpipe member in accordance with the present invention.

[0033]FIG. 16 is an illustration showing an example of a construction ofthe solid product removal apparatus of FIG. 15.

[0034]FIG. 17 is a view showing an exhaust gas processing system for asemiconductor manufacturing apparatus.

PREFERRED EMBODIMENTS OF THE INVENTION

[0035] The present invention will be described in more detail by way ofembodiments with reference to the accompanying drawings.

[0036]FIG. 1 is a view showing an example of the construction of anexhaust gas abatement device for carrying out a method for preventing anadherence of a solid product in a gas exhaust pipe member in accordancewith the present invention. In FIG. 1, reference numeral 1 stands for anexhaust gas abatement device for removing a hazardous ingredient from anexhaust gas containing an ingredient forming a solid product and thehazardous ingredient. The exhaust gas abatement device 1 is providedwith a main pipe member 2 through which exhaust gas EG flows, and theexhaust gas EG flown into an inlet la of the main pipe member 2 passesthrough the main pipe member 2 and is introduced into a reaction section3 where hazardous ingredients containing a solid product are to beremoved.

[0037] The reaction section 3 may be of any type, whether it is of a drytype with a reagent for adsorption of a hazardous ingredient filledtherein or it is of a wet type capable of removing a hazardousingredient by exposure of exhaust gas to water or it is of a burningtype or it is of a catalyst-reactive type, or it may be of a typecombining one with the other. The main pipe member 2 may be formed so asto allow a high-temperature inert gas having a high temperature to flowtherethrough via an inert gas inlet pipe member 5 from ahigh-temperature inert gas source 4 to prevent adhesion of the solidproduct to the inner wall of the main pipe member 2 by heating the innerwall of the main pipe member 2 with the high-temperature inert gas. Inthe example of the construction as shown in this drawing, the main pipemember 2 is provided with a temperature sensor 6 composed of athermocouple or the like, and a temperature measurement value with thetemperature sensor is subjected to feed-back to the high-temperatureinert gas source 4 to control the inner temperature inside the main pipemember 2 to a given temperature at which no solid product sticks.However, the high-temperature inert gas source 4 can also be set inadvance to a given fixed temperature in accordance with conditions forusage of the exhaust gas abatement device 1, without using such afeed-back control.

[0038]FIG. 2 is a view showing another example of the exhaust gasabatement device in accordance with the present invention. As shown inFIG. 2, the portions provided with the same reference numerals as inFIG. 1 indicate the portions identical thereto or corresponding thereto.The same are also be applied to the other drawings. Reference numeral 7stands for a bypass pipe member having a bypass valve 8, and the bypasspipe member 7 is connected to the main pipe member 3 at an inlet(upstream) side of the reaction section 3 and to the main pipe member 2at an outlet (downstream) side of the reaction section 3. The bypasspipe member 7 has a role for flowing the exhaust gas EG through thebypass pipe member 7 by opening the bypass pipe member 8 as problemssuch as a rise of pressure due to clogging in the main pipe member 2 orat the reaction section 3 with ingredients contained in the exhaust gasEG. In the example of the construction as shown in FIG. 2, the main pipemember 2 at the inlet side and the outlet side of the reaction section 3is provided with valves 9 and 10, respectively. Therefore, the reactionsection 3 can be subjected to maintenance upon an occurrence of troublesin the manner as described above by closing and stopping these valves.

[0039] In the example of the construction of FIG. 2, an inert gas havinga high temperature can be flown to the bypass pipe member 7 and the mainpipe member 2 through branched inert gas inlet pipe members 5 and 5′,respectively. As the bypass pipe member 8 is closed, the inert gasintroduced into the bypass pipe member 7 is allowed to flow into themain pipe member 2 at the upstream side to block entry of exhaust gasinto the bypass pipe member and prevent a solid product from adhering tothe bypass pipe member.

[0040]FIG. 3 shows another example of introduction of a high-temperatureinert gas into the bypass pipe member 7. In this example, thehigh-temperature inert gas G can be blown onto the bypass pipe member 8from a high-temperature inert gas inlet pipe member 11 to heat the innerwall of the bypass pipe member 7 therewith and also heat the bypass pipemember 8 to a sufficiently high temperature, thereby making it possibleto prevent a solid product from adhering to the bypass pipe member 8.

[0041] As shown in FIG. 4, the main pipe member 2 is provided with abranch pipe member 12, and a pressure gauge 13 is mounted at the tip ofthe branch pipe member. The pressure gauge 13 can sense a state ofclogging of the main pipe member 2 with a solid product stuck in themain pipe member by measuring the pressure in the main pipe member. Asshown in this drawing, the branch pipe member 12 is provided with thehigh-temperature inert gas inlet pipe member 11 connected to thehigh-temperature inert gas source 4 so as to blow a high-temperatureinert gas onto the pressure gauge 13 to purge the exhaust gas enteringinto the branch pipe member 12 and at the same time heat the pressuregauge 13, thereby making it feasible to prevent adhesion of the solidproduct thereto.

[0042] As shown in FIG. 5(a), the conventional apparatus is constructedin such a manner that a heater 16 is wound on the outside of the mainpipe member 2 made by SUS, for example, and uses the method that themain pipe member 2 is heated (by heating energy Q2) from the outsidewith the heater 16. Therefore, a heat-radiating energy Q1 becomes sohigh that a heating efficiency becomes too low. On the other hand, theapparatus according to the present invention is constructed in such amanner that the high-temperature inert gas G is flown through the insideof the main pipe member 2 made by SUS, for example, and the main pipemember is heated from the inner wall thereof (as shown in FIG. 5(b)) sothat the apparatus according to the present invention has aheat-radiating energy W lower than that of the conventional one.Therefore, the apparatus according to the present invention can heat theinside of the pipe member efficiently.

[0043]FIG. 6 is a view showing an example of the construction of thewet-type exhaust gas abatement device provided with the solid productremoval apparatus in accordance with the other example of the presentinvention. As shown in this drawing, the wet-type exhaust gas abatementdevice 1 has a similar structure to the system as described above, whichis composed of the main pipe member 2 through which an exhaust gasflows, the reaction section 3, and an exhaust pipe member 16 (adownstream portion of the main pipe member) through which to flow theexhaust gas that was rendered non-hazardous.

[0044] The reaction section 3 may be of a liquid-dispersing type inwhich an exhaust gas is exposed to water in a form of mist, moisture orthe like, or of a gas-dispersing type in which exhaust gas is dispersedin reserved water and passed therethrough or of a type in which thesetypes are combined together. As is similar to the examples as describedabove, the high-temperature inert gas can be introduced in the main pipemember 2 through the inert gas inlet pipe member 5 from thehigh-temperature inert gas source 4. In addition, rinsing water can beintroduced from the rinsing water source 18 through a rinsing waterinlet pipe member 20.

[0045] For the wet-type exhaust gas abatement device 1 having theabove-mentioned construction, a humidity within the main pipe member 2becomes so high at the position immediately in front of the reactionsection 3 that, in the case where the exhaust gas to be processedcontains an ingredient that may form a solid product upon reaction withwater, the solid product is likely to be formed, adhere to and depositon the portion immediately in front of the reaction section 3 of themain pipe member. In this embodiment, however, the solid product can beeffectively removed by flowing rinsing water through the portion fromthe rinsing water inlet pipe member 20. As the rinsing water, there maybe used water or an agent. Further, adherence and deposit of the solidproduct can be prevented by introducing the high-temperature inert gasinto the main pipe member 2 through the inert gas inlet pipe member 5from the high-temperature inert gas source 4 in substantially the samemanner as described in the examples on the basis of FIGS. 1 to 5.

[0046] For the wet-type exhaust gas abatement device as shown in FIG. 6,the inside of the main pipe member 2 is provided with a detector means14 composed of a thermocouple or the like for detecting a state of theadherence of a solid product stuck to the inner wall face of the mainpipe member 2. An amount of the rinsing water supplied from the rinsingwater source 18 can be controlled on the basis of the detection resultsof the detector means 14. The detector means 14 may be composed of apressure detector of a type capable of detecting pressure in the mainpipe member 2 or a photosensor of a type capable of detecting a state ofadherence of a solid product adhering to the inner wall face of the mainpipe member 2. The detector means 14 may be mounted at any optionalposition as long as it can monitor the state of the adherence of thesolid product in the main pipe member 2.

[0047] Further, the wet-type exhaust gas abatement device as shown inFIG. 6 is provided with a temperature sensor 15 composed of athermocouple or the like at an optional position on the downstream sidefrom the inert gas inlet pipe member 5 of the main pipe member 2. A flowrate of the high-temperature inert gas to be introduced into the mainpipe member 2 from the high-temperature inert gas source 4 can becontrolled on the basis of the output of the temperature sensor 15,thereby controlling the inner temperature of the main pipe member 2 to agiven temperature that can facilitate drying of the inner wall of themain pipe member 2. It is to be noted herein, however, that atemperature sensor of this type is not always needed and that heatingwith the high-temperature inert gas from the high-temperature inert gassource 4 can be controlled on the basis of a state of use of thewet-type exhaust gas abatement device or a state of introduction ofrinsing water. Moreover, as the heating means for drying the inner wallface of the main pipe member, there may be used, for example, a varietyof means, including but being not limited to means for winding a heaterabout the outer face of the main pipe member.

[0048]FIG. 7 illustrates an example of the specific construction forsupplying rinsing water to the main pipe member 2 from the rinsing waterinlet pipe member 20 as shown in FIG. 6. The rinsing water inlet pipemember 20 is provided with a nozzle 31 having a plurality of rinsingwater spray holes at the tip thereof to spray rinsing water in a showerform towards the inner wall face of the main pipe member 2 from therinsing water source 18. In the apparatus capable of preventing theadherence and deposit of a solid product with rinsing water, it ispreferred that rinsing water to be fed into the main pipe member isallowed to flow in the same direction as the flow direction of theexhaust gas in the main pipe member leading to a reactor of the exhaustgas abatement device from the vacuum pump. In the example as shown inFIG. 7, a connecting portion of the main pipe member 2 connecting to thereactor 3 is disposed extending in a vertical direction, and the nozzle31 is disposed so as to allow the rinsing water to feed downward in theconnecting portion thereof. Therefore, the rinsing water can be flowndownward as in the direction identical to the flow passage of theexhaust gas in the connecting portion thereof.

[0049]FIG. 8 shows another example of the construction for the supply ofrinsing water into the main pipe member. In this example, the tip of therinsing water inlet pipe member 20 is connected to a rinsing waterjacket member 32 disposed on the outer periphery of the main pipe member2, and the rinsing water fed to the rinsing water jacket member 32 canbe fed to the inner wall of the main pipe member through a number ofrinsing water spraying holes (not shown) disposed through the pipe wallof the main pipe member 2.

[0050]FIG. 9 illustrates a further example of the construction for thesupply of rinsing water into the main pipe member 2. In this example, arinsing water jacket member 32 is disposed at the outer periphery of themain pipe member 2 and a plurality of nozzles 33 communicating with therinsing water jacket member 32 are provided in the main pipe member 2.The rinsing water is fed to the rinsing water jacket member 32 throughthe rinsing water inlet pipe member 20 from the rinsing water source 18,and the rinsing water is then fed to the main pipe member 2 from thenozzles 33 and allowed to flow along the inner wall face of the mainpipe member.

[0051]FIG. 10 is a view showing another example of the construction ofthe rinsing water inlet pipe member of the wet-type exhaust gasabatement device with the solid product removal apparatus in accordancewith the present invention. In this example, the main pipe member 2 isprovided with a coating 34 made of a resin material on the inner facethereof. The coating makes it difficult for a solid product to adhere tothe inner wall of the main pipe member 2, and at the same time for waterdrops of rinsing water to remain on the inner wall of the main pipemember 2 after rinsing with the rinsing water. Further, an introductionportion 35 of the main pipe member 2 toward the reaction section 3 isconnected to the reaction section 3 in a diagonal direction in order todecrease deposit ion of a solid product to be washed away and flown withthe rinsing water on the introduction portion 35. This construction issuitable for the case, for example, where the reaction section 3 is madeof a resin material or where the pipe member cannot be heated to a hightemperature.

[0052]FIG. 11 is a view showing another example of the construction ofthe wet-type exhaust gas abatement device provided with the solidproduct removal apparatus in accordance with the present invention. Inthis example, the rinsing water inlet pipe member 5 is connected to theinert gas inlet pipe member 7 before introduction into the main pipemember 2. This construction can introduce the rinsing water into themain pipe member 2 after being heated to a high temperature with thehigh-temperature inert gas. Heating the rinsing water to a hightemperature in the manner as described above can dissolve the solidproduct stuck to the inner wall of the main pipe member 2 with therinsing water at a high temperature and remove it promptly.

[0053]FIG. 12(a) illustrates another example of means for feedingrinsing water to the main pipe member 2, as shown in FIGS. 7 and 9.

[0054] In the example as shown in FIG. 12(a), a first rinsing waterinlet pipe member 20 and a second rinsing water inlet pipe member 20′are connected to each other at a position spaced at a given interval inthe axial direction of the main pipe member 2 leading to the reactor 3of the wet-type exhaust gas abatement device. The means for feeding therinsing water into the main pipe member 2, as shown in FIGS. 7 to 9, isprovided in order to rinse off a solid product D (as shown in FIG.12(c)) stuck in a gas-liquid interface I formed in the main pipe memberclose to the reactor 3 in the manner as described above. Basically, asshown in FIG. 12(b), a rinsing water feed hole is provided at a positionclose to the top end of the solid product D stuck therein. In this case,the solid product D can be rinsed off, however, a fresh solid product D1(as shown in FIG. 12(b)) may also be caused to adhere under supply ofthe rinsing water at an upstream side (at an upper position) (of themain pipe member 2) from the position at which the rinsing water is fed.The solid product D1 can be turned into a size smaller than the solidproduct D rinsed off with the rinsing water, but it is preferable toremove also the fresh solid product D1. The example as shown in FIG.12(a) is constructed in such a manner that such a fresh solid product asthe solid product D1 can also be removed.

[0055] In the rinsing work according to this example, the rinsing wateris fed at a given periodical interval from the first rinsing water inletpipe member close to the reactor 3, and the solid product D deposited onthe inner face of the main pipe member close to the gas-liquid interfaceI can be rinsed off. On the other hand, the second rinsing water inletpipe member 20′ disposed at the upper position far apart from thereactor 3 than the first rinsing water inlet pipe member 20 can feedrinsing water at a longer periodical interval than the first rinsingwater inlet pipe member 20 (that is, the rinsing water can be fed withthe second rinsing water inlet pipe member 20′ at every one time per agiven number of times of the feeding of the rinsing water with the firstrinsing water inlet pipe member 20), and the total period of time forfeeding the rinsing water needed for the rinsing work by the secondrinsing water inlet pipe member 20′ can be rendered shorter than thetotal period of time for feeding the rinsing water needed for therinsing work by the first rinsing water inlet pipe member 20.

[0056] Even by feeding the rinsing water with the second rinsing waterinlet pipe member 20′ in the manner as described above, another solidproduct D2 may be adhering to and deposit on the inner face of the mainpipe member at the upstream side from the position of feeding therinsing water. The amount of the adhering solid product D2 isconsiderably smaller than the amount of the solid product D1 produced bythe first rinsing water inlet pipe member 20, so that the deposit of thesolid product D2 in such a smaller amount can be removed. Therefore, ifrinsing water inlet pipe members having equivalent actions are providedon the main pipe member in a spaced apart relation in a verticaldirection thereof, an amount of finally remaining adhered solid product,which corresponds to the solid product D2 as in the above-mentioned casewhere two rinsing water inlet pipe members are disposed, can be reducedin a manner of geometric series. More specifically, it is appropriatethat, for instance, an amount, a frequency of introduction of rinsingwater with each rinsing water inlet pipe member, and so on, aredetermined by an amount of a solid product deposited on the inner faceof the main pipe member. At this end, an amount of the solid productdeposited on the inner face of the main pipe member may be detected bymethods including but being not limited to a method for determining anamount of the solid product in response to the results of detection witha sensor mounted for detecting an amount of the solid product depositedat a given position in the main pipe member or a method for determiningan amount of the solid product under conditions fixed in advance inaccordance with the status of operations of the reactor or the like. Asolubility of some solid products in water may be temperature-dependent,and solubility in water of many of them may increase as the temperaturearises. Examples of such solid products include, but are not limited to,a reaction product, HBO₃, resulting from a reaction between BCl₃ andwater and a reaction product, Si₂, resulting from a reaction betweenSiC₄ and water. It is preferred, therefore, to elevate the temperatureof the rinsing water for these solid products, but the elevation of thetemperature of the rinsing water, however, may rather increase thepossibility of forming a solid product in the vicinity of a portion atwhich the rinsing water is being fed. The cause for this may be due toan increase in a velocity of the reaction with a gaseous ingredient withthe rinsing water for forming a solid product due to a rise in thetemperature of the rinsing water. Therefore, in order to decrease theformation of such solid products, it is preferred that the temperatureof the rinsing water in the vicinity of the top edge of the rinsingwater on the inner face of the main pipe member be decreased to thelowest possible level, while the rinsing water as a whole is kept at ahigh temperature. With these points taken into account, in the exampleas shown in FIG. 14, the rinsing water can be fed in a temperaturedistribution as described above by feeding rinsing water H having ahigher temperature from the first rinsing water inlet pipe member 20 andrinsing water C having a lower temperature from the second rinsing waterinlet pipe member 20′.

[0057] The rinsing water inlet pipe member is mounted on the main pipemember in the vicinity of an inlet of the reactor 3 for the wet-typeexhaust gas abatement device in the manner as shown in FIG. 12(a), and agas containing BCl₃ was subjected to processing experiments (Experiments#1, #2 and #3) for rinsing a solid product adhering to the inner face ofthe main pipe member under conditions as will be described below.

[0058] (Conditions of Gas)

[0059] Flow Rate of Gas: 10 slm

[0060] Concentration of BCl₃: 10%

[0061] (Conditions of Feeding Rinsing Water)

[0062] Feeding Interval:

[0063] Experiment #1: No rinsing water fed.

[0064] Experiment #2: Feeding for 10 seconds and ceased feeding for 5minutes and 50 seconds (1 cycle=6 minutes)

[0065] Experiment #3: Feeding for 10 seconds and ceased feeding for 5minutes and 50 seconds (1 cycle=6 minutes)

[0066] Feeding Modes:

[0067] Experiment #2: the rinsing water inlet pipe member 20 only wasused.

[0068] Experiment #3: In one cycle, feeding 9 times from the rinsingwater inlet pipe member 20 and then feeding once from the rinsing waterinlet pipe member 20′.

[0069] Amount of Feeding:

[0070] Experiment #2: 2.4 liters per minute

[0071] Experiment #3: 2.4 liters per minute (total amount)

[0072] Period of Experiment: 120 minutes

[0073] After the completion of the experiments, powdery materials stayedat the portion leading from the main pipe member to the reactor wasdissolved, and the concentration of boron (B) in water was measured todetermine an amount of an adhering solid product as H₃BO₃. The followingtable indicates the results of the above experiments. Gas Inlet PortionInner Face of Main Pipe Member of Reactor Experiment #1 0.01 gram  5.1gram Almost clogged Experiment #2 0.93 gram 0.02 gram The solid productwas adhering in a large amount between two rinsing water inlet pipemembers. An almost half of the pipe member was clogged. Experiment #30.03 gram 0.01 gram The solid product was adhering in a small amount onthe upper portion of the rinsing water inlet pipe member. The state ofthe pipe member was substantially the same as before the experiment.

[0074] In the above examples, two rinsing water inlet pipe members 20and 20′ are provided designing so as to cause the rinsing water inletpipe member on the upstream side of the main pipe member to remove thesolid product derived by the introduction of the rinsing water from therinsing water inlet pipe member at the downstream side thereof. It isfound therefrom, however, that the relationship of the positions of therinsing water inlet pipe members is not limited to this embodiment andthat, in summary, in order to allow the solid product formed by therinsing water fed previously, adhering and deposited to be removed, therinsing water to be fed later is fed such that the top end thereof onthe inner face of the main pipe member reaches above the top end of thesolid product formed beforehand.

[0075] For instance, when description is made taking the example asshown in FIG. 12, the second rinsing water inlet pipe member 20′ may bemounted at a position lower than the first rinsing water inlet pipemember. Moreover, if it is possible to feed the rinsing water in amanner so as to satisfy the conditions described above, it is not neededto provide the rinsing water inlet pipe members in a vertically spacedapart relationship in plural stages along the main pipe member. In otherwords, the rinsing water inlet pipe member can be disposed in a singlestage (that is to say, a rinsing water inlet pipe member is disposed ata single position of the main pipe member), and the rinsing action canbe done in substantially the same manner as described in the aboveexamples by changing the pressure of feeding the rinsing water.

[0076] When the rinsing water is fed into the main pipe member throughthe rinsing water inlet pipe member, it is preferred that the locationof the inner face of the main pipe member where it becomes wet with thefed rinsing water due to scattering of the rinsing water upon strikingonto the inner face of the main pipe member does not expand upwardlyabove a given location. It is preferred, therefore, that the tip opening21 of the rinsing water inlet pipe member 20 be disposed in a directiontangent to the inner face of the main pipe member 20, as shown in FIG.13. Moreover, it is preferred that the tip opening 21 be disposed so asto be directed horizontally or downwardly, not upwardly, from the pointof view of preventing the rinsing water from scattering or controllingthe maximal height of the fed rinsing water on the inner face of themain pipe member (controlling the position of the top edge thereof). Therinsing water discharged from the tip opening 21 into the inner face ofthe main pipe member flows downward on the inner face of the main pipemember while circulating around the central axial line of the inner facethereof under a centrifugal force. The maximal height at which therinsing water can reach on the inner face of the main pipe member can bedetermined by the flow speed of the rinsing water flowing downward.Therefore, in the case where the rinsing water inlet pipe member isdisposed in a single stage in the manner as described above,substantially the same effects can be achieved by controlling the flowspeed of the rinsing water as the rinsing action is carried out bymounting the rinsing water inlet pipe members in plural stages in themanner as described above.

[0077]FIG. 15 is a view showing an example of the construction of thewet-type exhaust gas abatement device with the solid product removalapparatus according to another example of the present invention. Asshown in FIG. 15, the wet-type exhaust gas abatement device 1 hassubstantially the same structure as those described above, which iscomposed of the main pipe member 2 through which to flow exhaust gas,the reaction section 3, and the gas discharging pipe member 16 throughwhich to flow a non-hazardous exhaust gas. The main pipe member 2 isdesigned in substantially the same manner as described above tointroduce a high-temperature inert gas from the high-temperature inertgas source 4 through the inert gas inlet pipe member 5 to control theformation of a solid product in the main pipe member. In this example,in addition thereto, a solid product removal means 40 for scraping thesolid product stuck to a portion of the main pipe member 2 at thereactor 3 is provided at the portion of the main pipe member 2 insubstantially the same manner as described above.

[0078] A specific construction of the solid product removal means 40 isillustrated in FIG. 16. As shown in this drawing, the solid productremoval means 40 may be composed of a drive means 42 such as a motor orthe like, disposed at the top end of a pipe member portion 2′ extendingvertically from the reactor 3 of the main pipe member 2 and a scrapingmember means 44 disposed so as to be movable vertically in the pipemember portion 2′ by the drive means for scraping the solid productstuck on the inner face of the pipe member portion. The scraping membermeans may be of any type that can scrape the solid product by sliding onthe inner face of the pipe member portion 2′, and it may include but isnot limited to a type in the form of a disc, spiral, bar or the like ora type capable of rotating in addition to moving vertically.

[0079] In this drawing, reference numeral 46 stands for a rinsing waterinlet pipe member so disposed as to rinse off the solid product adheringto the scraping member means 44 and the inner face of the pipe memberportion 2′ by appropriately feeding rinsing water into the pipe memberportion 2′. In FIG. 15, reference numeral 14 stands for a detector meansfor detecting a state of the adherence of the solid product adhering tothe inner wall face of the pipe member portion 2′ by detecting thepressure within the main pipe member. Reference numeral 15 stands for atemperature sensor for controlling the high-temperature inert gas source4.

INDUSTRIAL APPLICABILITY

[0080] Although the present invention is particularly suitable for a gasexhaust system of a semiconductor manufacturing apparatus, it is to beunderstood that it is not limited to the gas exhaust system thereof andit can be applied to a variety of gas exhaust systems.

1. A solid product removal apparatus for removing a solid productadhering to an inner face of a gas exhaust pipe member, characterized inthat the solid product removal apparatus is provided with a rinsingwater inlet pipe member having a tip opening located in a gas exhaustpipe and feeding rinsing water into the inner face of the gas exhaustpipe member from the tip opening.
 2. The solid product removal apparatusaccording to claim 1, characterized in that said tip opening has anopening at the inner face of the gas exhaust pipe member.
 3. The solidproduct removal apparatus according to claim 2, characterized in thatsaid rinsing water inlet pipe member is disposed on a periphery of thegas exhaust pipe member and provided with a rinsing water jacket memberin a ring-shaped form for receiving rinsing water and that said tipopening communicates with the rinsing water jacket member and extendsthrough a pipe wall of the gas exhaust pipe member up to the inner faceof the gas exhaust pipe member.
 4. The solid product removal apparatusaccording to claim 1, characterized in that said tip opening is providedwith a nozzle for discharging rinsing water, aligned in a passage of anexhaust gas in the gas exhaust pipe member.
 5. The solid product removalapparatus according to any one of claims 1 to 4, characterized by aheating means for heating the gas exhaust pipe member to evaporaterinsing water remaining on the inner face of the gas exhaust pipe memberafter introduction of the rinsing water.
 6. The solid product removalapparatus according to claim 5, characterized in that the heating meansincludes a gas source for feeding a high-temperature gas having a hightemperature for feeding the high-temperature gas into the gas exhaustpipe member.
 7. The solid product removal apparatus according to claim6, characterized in that the high-temperature gas is gas inert toexhaust gas.
 8. The solid product removal apparatus according to any oneof claims 1 to 7, characterized in that a plurality of said tip openingsare provided in a relationship so as to be spaced apart at a giveninterval in a direction of flow of the exhaust gas in the gas exhaustpipe member.
 9. The solid product removal apparatus according to any oneof claims 1 to 8, characterized in that a scraping member means forscraping a solid product adhering to the inner face of the gas exhaustpipe member is disposed in the gas exhaust pipe member so as to beslidably movable in the gas exhaust pipe member in a lengthwisedirection thereof.
 10. A solid product removal method for removing asolid product adhering to an inner face of a gas exhaust pipe member,characterized in that the method comprises the steps of: rinsing off aprimary solid product formed upon reaction of an ingredient contained inexhaust gas with a moisture present in the gas exhaust pipe member andadhering to the inner face of the gas exhaust pipe member by feeding aprimary rinsing water to the primary solid product; and rinsing off asecondary solid product formed newly upon reaction with the primaryrinsing water and adhering to the inner face of the gas exhaust pipemember by feeding a secondary rinsing water to the secondary solidproduct.
 11. The solid product removal method according to claim 10,characterized in that: the gas exhaust pipe member is provided with afirst rinsing water supply inlet and a second rinsing water supply inletin a spaced relationship apart at a given interval along a direction offlow of exhaust gas; the primary rinsing water is fed from the firstrinsing water supply inlet; and the secondary rinsing water is fed fromthe second rinsing water supply inlet.
 12. The solid product removalmethod according to claim 10, characterized in that the primary rinsingwater and the secondary rinsing water are fed to the primary solidproduct and the secondary solid product by feeding the primary rinsingwater and the secondary rinsing water, respectively, from a singlerinsing water supply inlet disposed in the gas exhaust pipe member at adifferent pressure so as to adjust a range of distribution of theprimary rinsing water and the secondary rinsing water in the gas exhaustpipe member.
 13. A solid product removal apparatus for removing a solidproduct adhering to an inner face of a gas exhaust pipe member,characterized by a high-temperature gas inlet means for introducing gashaving a high temperature to heat the inner face of the gas exhaust pipemember by introducing the high-temperature gas into the gas exhaust pipemember.
 14. The solid product removal apparatus according to claim 13,characterized in that the gas inlet means is provided with an openingfor discharging the high-temperature gas toward a given portion insidethe gas exhaust pipe member.
 15. The solid product removal apparatusaccording to claim 13 or 14, characterized in that the gas exhaust pipemember is provided with a scraping member means therein so as to beslidably movable in the gas exhaust pipe member in a lengthwisedirection thereof and scrape the solid product adhering to the innerface of the gas exhaust pipe member.
 16. A solid product removalapparatus for removing a solid product adhering to an inner face of agas exhaust pipe member, characterized in that the gas exhaust pipemember is provided with a scraping member means therein so as to beslidably movable in the gas exhaust pipe member in a lengthwisedirection thereof and scrape the solid product adhering to the innerface of the gas exhaust pipe member.
 17. An exhaust gas processingsystem for the production of semiconductors, comprising: a semiconductormanufacturing apparatus with a vacuum chamber for processing asemiconductor; a vacuum pump for discharging gas used in the vacuumchamber from the vacuum chamber; a wet-type exhaust gas abatement devicefor processing gas discharged with the vacuum pump into a non-hazardousgas; a first pipe member connecting the semiconductor manufacturingapparatus to the vacuum pump; a second pipe member connecting the vacuumpump to the exhaust gas abatement device; and a solid product removalapparatus disposed in the second pipe member for removing a solidproduct formed upon reaction of exhaust gas with a moisture from thewet-type exhaust gas abatement device and stuck to an inner face of aconnecting portion thereof; characterized by: a rinsing water inlet pipemember having a tip opening located in the second pipe member forfeeding rinsing water into the inner face of the second pipe member fromthe tip opening thereof.
 18. The exhaust gas processing system accordingto claim 17, characterized in that the rinsing water inlet pipe memberis provided with a rinsing water jacket member in a ring-shaped form ona periphery of the second pipe member and that the tip openingcommunicates with the rinsing water jacket member and extends through apipe wall of the second pipe member up to the inner face of the pipemember.
 19. The exhaust gas processing system according to claim 17 or18, characterized in that the tip opening is provided with a nozzlealigned with an exhaust gas passage of the second pipe member fordischarging rinsing water.
 20. The exhaust gas abatement deviceaccording to any one of claims 17 to 19, characterized by ahigh-temperature inert gas source of a high-temperature inert gas havinga high temperature for feeding the high-temperature inert gas into theconnecting portion to heat and evaporate the rinsing water remaining inthe second pipe member after introduction of the rinsing water.
 21. Theexhaust gas abatement device according to any one of claims 17 to 20,characterized in that a plurality of the tip openings of the rinsingwater inlet pipe member are provided in a spaced relationship apart at agiven interval in a lengthwise direction of the second pipe member. 22.The exhaust gas abatement device according to any one of claims 17 to21, characterized in that the second pipe member is provided with ascraping member means therein so as to be slidably movable in the pipemember along a lengthwise direction thereof to scrape the solid productadhering to the inner face of the pipe member.